The number of new cars made in the UK fell 31.5% in August from the same month a year earlier, industry figures have shown.
There were 56,737 cars made last month, the Society of Motor Manufacturers and Traders (SMMT) said.
But the number of cars built for the UK market reached a near five-year high as the car scrappage scheme boosted sales.
The SMMT called for the scheme, which was introduced in May, to be extended, saying recovery was still fragile.
The drop in production was bigger than the 17.9% fall seen in July, but many car plants have extended shutdowns in August.